1. Field of the Invention
The present invention relates to a method for building a floor that is designed to make a direct use of the heat stored in the earth and the like, and the construction of the floor that will be built by using such method.
2. Description of the Prior Art
Generally, the earth is kept at a constant temperature in relation to the air in the atmosphere surrounding it. That is, the temperature will remain almost unchanged despite the change in the surrounding air temperature that occurs from season to season. Thus, the earth temperature is relatively warm in winter, and is relatively cool in summer. In order to take advantage of the fact that the earth temperature will change little throughout the year, that is, from season to season, a system that is called a passive solar system is proposed, and is currently available in different types. This system is actually installed in structures such as houses. Typically, the passive solar system is designed to control the temperature of the air in the space within the house by allowing the air to circulate after it touches the earth. The system is based on the concept of exchanging heat. The air may become warmer or cooler by exchanging its heat with the heat stored in the earth (herein after referred to as the stored heat), and may then be circulated through the interior of the house. As such, the system has a problem in its thermal efficiency.
As an alternative to the passive solar system, another system is proposed which is designed to make a direct use of the stored heat and convey the stored heat to the flooring directly without the medium of the air. To convey the stored heat to the flooring directly, it is necessary to provide a thermal connection between the earth and flooring. Particularly in post-type flooring, where intermediate free space is provided between the earth and flooring to allow air to circulate, this thermal connection will become useless. In order to address this problem, another technique has been proposed. In this technique, a gravel bed is provided on the earth under the floor, and concrete is placed on the gravel bed on which the underfloor concrete layer is formed. Then, the flooring finish boards or slabs are directly applied upon the upper surface of the underfloor concrete layer. This technique is known as the xe2x80x9cgravel bed air-conditioning systemxe2x80x9d, which was proposed by the Japanese architect, Kanao Sakamoto (page 24, the Nihon Keizai Shinbun issued on Jan. 30, 1980 and page 15, the Mainichi Shinbun issued on Feb. 22, 1980).
Typically, in conventional structures such as houses, the floor is built by placing a groundsill, or simply sill, on its corresponding continuous footing, also referred to as wall footing or column footing, which is usually made of reinforced concrete. Generally, the groundsill is provided for supporting the columns or posts that are mounted upright thereon, and each groundsill is provided on the location of each corresponding one of the compartments or rooms to delimit the adjacent compartments or rooms from each other. Generally, a continuous footing includes an outer circumferential continuous footing that surrounds the outside of the structure, and an inner continuous footing that is installed inside the outer circumferential continuous footing. The outer and inner continuous footings, each of which corresponds to each groundsill, are provided separately.
In the conventional technique described above, errors may be introduced when the flooring finish boards or slabs are directly applied upon the upper surface of the underfloor concrete layer. Thus, the errors that are allowed for when the flooring finish boards or slabs are applied on the upper surface of the underfloor concrete layer must be kept as minimal as possible. When an ordinary plaster trowel, long bar or plate is used to flatten the upper surface of the underfloor concrete layer, it may cause errors that are on the order of 1 to 10 mm. In order to finish the underfloor concrete layer so that it can have horizontal surface uniformity over a wide area, complicated steps are involved, which may have an unfavorable effect on the working efficiency. This is the case particularly in recent years when specialized or experienced engineers have not been available. Alternatively, mortar may be applied upon the upper surface of the underfloor concrete layer after the concrete becomes hardened, and the thickness of the applied mortar coating may then be adjusted to provide the horizontal surface uniformity. When this operation takes place, it may introduce further errors that must be corrected. Thus, this must be carried out with extreme care.
The earth may be warmed when its surrounding ground level or surface is warmed by being exposed to sunlight and the like, which may also make the earth under the floor warm. In addition, the underfloor concrete layer may also be warmed by the thermal energy that is produced within the house. The heat stored in the earth, coupled with the heat stored in the underfloor concrete layer, may also warm the gravel bed under the underfloor concrete layer. The inventor of the current application conducted experiments, and observed that the stored heat in the gravel bed would be the result of the combined action of xe2x80x9cthe thin air layer that is present among the adjacent gravel stonesxe2x80x9d, xe2x80x9cthe gravel stones themselvesxe2x80x9d and xe2x80x9cthe underfloor concrete layerxe2x80x9d, rather than the heat stored in the gravel stones themselves. It was also observed that the gravel layer within the closed space includes a lower layer located nearer to the ground level where the gravel stones still contain a slight amount of water, and in upper layer located farther from the ground level where the gravel stones are in a dry or non-water condition.
In the conventional technique, each continuous footing, which is usually constructed from reinforced concrete, is built for each corresponding groundsill that is being built thereon. Thus, each concrete form or mold must be built for each corresponding continuous footing so that each of the concrete forms can conform to each corresponding one of the continuous footings. The building and subsequent removing of the concrete forms, as well as the arranging of the reinforcing bars, must be carried out for each continuous footing. Those steps must be performed for each individual continuous footing being built, and therefore would require laborious and time-consuming operations. Particularly, when a structure being built, such as a house, has a number of small rooms inside that are delimited by walls from each other, each groundsill must be provided for each room, and each continuous footing must be provided for each corresponding groundsill.
The inventor of the current application has a prior Japanese patent application, which was laid opened to the public inspection under unexamined patent publication No. H10 (1998)xe2x80x94273948A and now patented under No. 3051850. The invention disclosed in this Japanese patent is designed to make effective use of the stored heat in the earth.
The inventor of the present application proposes to provides a further improvement over the prior invention that is disclosed in the above Japanese patent.
A first object of the present invention is to simplify the process of building the continuous footing, thereby improving the work efficiency. This object may be achieved by providing a continuous footing on a location that corresponds to the location of an outer circumferential groundsill being built that surrounds the outer circumference of a structure such as a house, and providing an inside groundsill integrally constructed with an underfloor concrete layer by burying the inside groundsill within the underfloor concrete layer. A part of the underfloor concrete layer at which the inside groundsill is buried has a projection extending downwardly from the underfloor concrete layer at a location that corresponds to a location of the inside groundsill being built. The inside groundsill is thereby built integrally with the projection of the underfloor concrete layer so that the inside groundsill can provide the desired mechanical strength and stability.
A second object of the present invention is to improve the working precision with which the flooring finish boards or slabs can be placed on the underfloor concrete layer. This object may be achieved by providing the outer circumferential groundsill and inside groundsill such that they can have respective upper edges flush with each other, providing an underfloor concrete layer by placing concrete on the planned location of the floor being built, and flattening the upper surface of the resulting underfloor concrete layer so that it can have horizontal surface uniformity, thereby facilitating the placement of the flooring finish boards or slabs on the underfloor concrete layer.
A third object of the present invention is to improve the working precision with which columns or posts can be mounted upright on the groundsills. This object may be achieved by providing column or post mounting means at the axial center of the upper surface of the inside groundsill, and using the lateral edges of the inside groundsill to flatten the upper surface of the underfloor concrete layer.
Briefly, all of the above objects may be attained by providing an inside groundsill inside the outer circumferential groundsill so that it can have its upper edge flush with that of the outer circumferential groundsill, and placing concrete for forming an underfloor concrete layer along the respective upper edges of the two groundsills.
One aspect of the present invention is to provide a method for building a floor wherein the floor is designed to make a direct use of the stored heat in the earth or the like. The method comprises:
(1) providing a continuous footing made of concrete on a location corresponding to a location of an outside groundsill surrounding the outer circumference of a structure being built, placing stones to cover all of the area on the planned floor location in such a manner that grooves or trenches may be formed along the location of an inside groundsill being built, and installing an outer circumferential groundsill on the continuous footing;
(2) providing an inside groundsill along the location of the same inside groundsill being built so that it can extend across the outer circumferential groundsill and can have its upper edge flush with that of the outer circumferential groundsill;
(3) providing an underfloor concrete layer by placing concrete along the respective upper edges of the outer and inside groundsills within the planned floor location; and
(4) after the underfloor concrete placed in step (3) becomes hardened, placing flooring finish boards or slabs on the upper surface of the underfloor concrete layer.
A second aspect of the present invention is to provide a method for building a floor, wherein the floor is designed to make a direct use of the stored heat in the earth or the like. The method comprises: providing a ruler across or between the groundsills so that the ruler can delimit the planned floor location and can be aligned with the respective upper surfaces of the groundsills, and using the upper surfaces of the groundsill and the ruler as a reference to flatten the upper surface of the underfloor concrete layer.
A third aspect of the present invention is to provide a method for building a floor, wherein the floor is designed to make a direct use of the stored heat in the earth or the like. The method comprises:
(1) providing a continuous footing made of concrete, placing stones to cover all of the area on the planned floor location surrounded by the concrete continuous footing, and building a groundsill on the concrete continuous footing;
(2) providing a ruler of any shape steel on the planned floor location so that the ruler can extend between the groundsills opposite each other and have its upper edge flush with that of the respective upper surfaces of the groundsills, the ruler serving as reference for flattening an underfloor concrete that is placed in step (3) below;
(3) placing concrete for forming an underfloor concrete layer along the upper edge of the flattening tool on the planned floor location; and
(4) after the underfloor concrete placed in step (3) becomes hardened, placing flooring finish boards or slabs on the upper surface of the underfloor concrete layer.
A fourth aspect of the present invention is to provide a method for building a floor wherein the floor is designed to make a direct use of the stored heat in the earth or the like. The method comprises:
(1) providing column or post mounting means on an inside groundsill; and
(2) then, placing the inside groundsill extending across outer circumferential footings.
A fifth aspect of the present invention is to provide a floor construction for a wood structure or house, wherein the floor construction is designed to make a direct use of the stored heat in the earth or the like. An outer circumferential groundsill surrounds the outer circumference of the structure or house being built. An inside groundsill is provided inside the outer circumferential groundsill. An underfloor concrete layer is installed on a stone layer within each of the outer circumferential groundsill and inside groundsill such that the underfloor concrete layer can have its upper surface flush with the respective upper edge of each of the groundsills. Flooring finish boards or slabs are placed on the upper surface of the underfloor concrete layer. The outer circumferential groundsill is built on a continuous footing made of concrete. The inside groundsill is secured at each of opposite ends to the lateral side of the outer circumferential groundsill or to the lateral side of another inside groundsill provided adjacent to the inside groundsill, and is buried within the underfloor concrete layer. A part of the underfloor concrete layer at which the inside groundsill is buried has a projection extending downwardly from the underfloor concrete layer.
A sixth aspect of the present invention is to provide a floor construction for a wood structure or house, wherein the floor construction is designed to make a direct use of the stored heat in the earth or the like. Column or post mounting means is previously provided at an axial center of the upper surface of the inside groundsill.
In each of the aspects of the present invention described above, the outer circumferential groundsill may primarily be made of steel materials such as H-shaped steel, steel pipes, and the like, or wooden materials.
In each of the aspects of the present invention described above, the inside groundsill is provided as an integral part of the underfloor concrete layer so that it can cooperate with the underfloor concrete layer, and may primarily be made of a steel material such as H-shaped steel or steel plate of a rectangular shape.
In each of the aspects of the present invention, the ruler may be provided at any required location across the outer circumferential groundsill, across the inside groundsill, or between the outer circumferential groundsill and inside groundsill.
In each of the aspects of the present invention, the column or post mounting means that is provided at the axial center of the inside groundsill may accept the column or post (mainly tubular column), allowing it to be mounted to the inside groundsill. To this end, the column mounting means may have a projection provided at the axial center and upper surface of inside groundsill for engaging the column or post, and the column or post may have a hole at the bottom surface to engage onto the projection. Alternatively, the column mounting means may include a cylindrical member for accepting the column or post, or may have a bolt hole or round hole for securing the column or post to the inside groundsill.
In each of the aspects of the present invention, the column or post mounting means is usually provided at the axial center and upper surface of the inside groundsill in the factory, and means for fine-adjusting the position or additional mounting means (mainly bolt holes or round holes) may be provided in the field.
In each of the aspects of the present invention, the stored heat in the earth or the like should be understood to mean the stored heat produced by the combined action of the stored heat in the earth, the heat of the gravel stones themselves, the heat carried by the air layer between the gravel stones, and the heat produced under the underfloor concrete layer or the flooring finish boards placed on the underfloor concrete layer.
Typically, the present invention may be embodied as follows.
A continuous footing made of concrete may be built on a location that corresponds to the location of a groundsill being built to surround the outer circumference of a structure such as a house. Within the continuous footing, a stone layer may be installed by placing stones to cover all over the area on the planned floor location. The stone layer includes grooves or trenches formed along the location of an inside groundsill being built. The groundsill surrounding the outer circumference of the structure, or outer circumferential ground, may be built on the continuous footing. Then, the inside groundsill may be built along the grooves or trenches to extend across the outer circumferential groundsill, such that the inside groundsill can have its upper edge flush with that of the outer circumferential groundsill. Next, within the planned floor location, concrete may be placed along the respective upper edges of the outside and inside groundsills to form an underfloor concrete layer. After the concrete that has been placed becomes hardened, flooring finish boards or slabs may be placed on the upper surface of the underfloor concrete layer. This may complete the floor that makes direct use of the heat stored (or stored heat) in the earth or the like.